Tubes and less sensitive speakers

The sanders magtec was developed for this type of speaker.they work well great synergy.the music room has one for sale around 4k.you can go to sanders sound website and read his white paper.enjoy the search

An inexpensive option would be a pair of PrimaLuna Evo 400 power amps in mono?  Each is capable of running with 8 KT150 tubes in Triode or Ultra Linear mode.  Just a thought.  Cheers.

The noble exchange between @jeffbij and atmashere is worth noting . Well done gentlemen .

I agree - nice job by both in providing clarity and reaching a unified view.

Regarding proper subwoofer integration, I would caution that while this is a valid approach, in my experience, it can also be quite challenging due to the true dipole dispersion of Maggies. A number of years ago I was running a set of Quad 2805 and Maggie 1.7i with Atma-Sphere amps and wanted to supplement with subwoofers. Unless the subs were truly fast enough to match the speed of the stats and planars and impeccably integrated, it tended to cause smearing through the frequency extreme because of interference between the subs and the speakers’ radically different rear dispersions. In my opinion it would be best to first address the amp / speaker matching to the best of your ability as this will deliver the optimal control and tone out of the speakers. Doing so will also make it easier to integrate subs if/when one is ready to do so.

In short, don't use subs as a band-aid solution, but only to improve upon performance that can already be gained elsewhere.

Also to answer the OP's original question, Audio Research and Magenpan have have had a nice love affair going on for some time now, so perhaps look into their amps.

I agree that with Ralph that if you're using the 3.7's and want to look at Atma-Sphere, look into the MA-1 and not any of the smaller models. I've been in the camp of trying to mate his smaller amps with autoformers on larger planars / stats and while it's pleasant, you won't get the best out of them. The MA-1 MK3.3 is highly recommended as long as you can handle the number and heat of the tubes.